A brush seal structure suitable for a squeeze film bearing fulcrum

Abstract

The application provides a brush seal structure suitable for a squeeze film bearing fulcrum, and the brush seal structure comprises: a rotor runway, a front plate and a back plate, and brush wires arranged between the front plate and the back plate, wherein the brush wires are composed of an upper half-ring brush wire and a lower half-ring brush wire to form a whole ring structure, and at least one of the brush wire diameter and the brush wire inclination angle of the upper half-ring brush wire and the lower half-ring brush wire is different. The brush seal structure provided by the application can bear different wear conditions of the upper half-ring and the lower half-ring through different diameters and inclination angles of the upper half-ring brush wire and the lower half-ring brush wire without changing the interface size and the overall structure of the brush seal. Compared with the traditional brush seal structure, the application can not only guarantee the sealing performance of the brush seal under pressure difference, but also bear the wear of the brush wire caused by the rotor sinking when the squeeze oil film is not established, thereby improving the reliability and service life of the brush seal.

Description

Technical Field

[0001] This application belongs to the field of sealing structure technology, and specifically relates to a brush seal structure suitable for the bearing support of extruded oil film bearings. Background Technology

[0002] Brush seals are commonly used gas sealing devices in the air systems of aircraft engines or gas turbines. Compared with traditional labyrinth seals, brush seals not only have better sealing characteristics, but are also a flexible contact dynamic sealing technology that can adapt to the instantaneous radial deformation or eccentric movement of the rotor.

[0003] A brush seal consists of a front plate, a back plate, and a tightly packed bundle of brush filaments sandwiched between them. The brush seal relies on the close contact between these neatly arranged, tightly packed brush filaments and the rotor to form a sealing surface, thus preventing upstream gas leakage and achieving a sealing effect. Traditional brush seals use bundles of tens of thousands, or even hundreds of thousands, of uniformly sized brush filaments. Due to the relatively flexible nature of the brush filaments, and the transient radial clearance changes or eccentric motion of the engine rotor and stator, along with extremely high-speed relative motion between the brush filaments and the rotor, varying degrees of wear occur when the brush filaments contact the rotor surface. Brush seals are typically used at bearing pivot rotors with compressed oil films. Because existing brush seals have uniform brush filament diameter and tilt angle, resulting in uniform stiffness and wear resistance, rotor sinking during the initial oil film formation stage exacerbates wear on the lower half of the brush filaments. This leads to increased gas leakage, reduced sealing performance, and a shorter service life for the brush seal. Summary of the Invention

[0004] The purpose of this application is to provide a brush seal structure suitable for the bearing pivot of a squeeze oil film bearing, so as to solve or alleviate at least one of the problems in the prior art.

[0005] The technical solution of this application is: a brush seal structure suitable for the bearing support of an extruded oil film bearing, the brush seal structure comprising:

[0006] Rotor track;

[0007] Front and back panels; and

[0008] The brush bristles are disposed between the front plate and the back plate, wherein the brush bristles are composed of an upper half-ring brush bristle and a lower half-ring brush bristle forming a complete ring structure, and the brush bristle diameter and brush bristle inclination angle of the upper half-ring brush bristles are different from those of the lower half-ring brush bristles.

[0009] The brush seal structure provided in this application can withstand different wear conditions on the upper and lower half-rings without changing the interface size and overall structure of the brush seal. By using different diameters and tilt angles for the brush filaments in the upper and lower half-rings, it can withstand different wear conditions on the upper and lower half-rings under different operating conditions. Compared with traditional brush seal structures, this application can not only ensure the sealing performance of the brush seal under pressure differential, but also withstand the wear on the brush filaments caused by rotor sinking when the squeezed oil film has not been established, thereby improving the reliability and service life of the brush seal.

[0010] In a preferred embodiment of this application, the brush filament diameter and the brush filament tilt angle of the upper half ring brush filament are different from those of the lower half ring brush filament.

[0011] In a preferred embodiment of this application, the brush bristles with larger diameters in the upper and lower half-ring brush filaments are located in the areas where the brush filaments are prone to wear.

[0012] In a preferred embodiment of this application, the brush bristles with larger diameters in the upper and lower half-ring brush filaments have a greater tilt angle.

[0013] In a preferred embodiment of this application, the front plate and the back plate are fixed by snap-fitting or welding.

[0014] In a preferred embodiment of this application, a coating is provided on the rotor track at the position corresponding to the brush filaments. Attached Figure Description

[0015] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0016] Figure 1 This is a schematic diagram of the brush seal structure of this application.

[0017] Figure 2 This is a schematic diagram of the brush bristles in this application. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0019] To address the severe wear of the brush seal structure caused by rotor sinking without altering the interface dimensions, and to increase the reliability and service life of brush seals applied at bearing supports with extrusion oil film, this application proposes a novel brush seal structure.

[0020] like Figure 1 and Figure 2As shown, the brush seal structure 10 provided in the application includes a front plate 11, brush bristles 12, a back plate 13, a rotor track 14, and a coating 15 on the track. The front plate 11 and the back plate 13 can be fixed by snap-fit ​​or welding, and the brush bristles 12 are disposed between the two. The outer surface of the rotor track 14 is coated with a coating 15 at the part that adapts to the brush bristles 12 to improve the wear resistance of the outer surface of the rotor track 14.

[0021] The brush bristles 12 consist of an upper ring bristle 121 and a lower ring bristle 122 forming a complete ring structure. At least one of the bristle diameter and the bristle inclination angle of the upper ring bristle 121 and the lower ring bristle 122 is different. In a preferred embodiment of this application, both the bristle diameter and the bristle inclination angle of the upper ring bristle 21 and the lower ring bristle 22 are different.

[0022] For example, in this embodiment of the application, in a conventional full-ring brush bristle, the lower half of the ring is more prone to wear. Therefore, in order to make the lower half-ring brush bristle 22 more wear-resistant, the lower half-ring brush bristle 22 can be made with a larger diameter than the upper half-ring brush bristle 21. At the same time, in order to solve the problem of increased brush bristle stiffness caused by increasing the brush bristle diameter, the brush bristle tilt angle of the lower half-ring brush bristle 22 can be increased to overcome the above-mentioned problem.

[0023] The brush seal structure provided in this application does not change the stiffness of the brush bristles—that is, it does not change the contact stress and wear rate between the brush bristles 12 and the coating 15 on the rotor track 14. Due to the increased diameter of the lower half-ring brush bristles 122, the wear of the lower half-ring brush bristles 122 is reduced, and the wear resistance of the lower half-ring brush bristles 122 is increased.

[0024] The brush seal structure provided in this application can withstand different wear conditions on the upper and lower half-rings without changing the interface size and overall structure of the brush seal. By using different diameters and tilt angles for the brush filaments in the upper and lower half-rings, it can withstand different wear conditions on the upper and lower half-rings under different operating conditions. Compared with traditional brush seal structures, this application can not only ensure the sealing performance of the brush seal under pressure differential, but also withstand the wear on the brush filaments caused by rotor sinking when the squeezed oil film has not been established, thereby improving the reliability and service life of the brush seal.

[0025] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A brush seal structure suitable for the bearing pivot of an extruded oil film bearing, characterized in that, The brush seal structure (10) includes: Rotor track (14); Front panel (11) and back panel (13); and The brush bristles (12) are arranged between the front plate (11) and the back plate (13), wherein the brush bristles (12) are composed of an upper half-ring brush bristle (21) and a lower half-ring brush bristle (22) forming a complete ring structure, and the brush bristle diameter and brush bristle inclination angle of the upper half-ring brush bristle (21) and the lower half-ring brush bristle (22) are different.

2. The brush seal structure for the bearing pivot of an extruded oil film bearing as described in claim 1, characterized in that, The brushes with larger diameters in the upper half-ring brush bristles (21) and the lower half-ring brush bristles (22) are placed in the areas where the brush bristles are easily worn.

3. The brush seal structure for the bearing pivot of an extruded oil film bearing as described in claim 2, characterized in that, The brush bristles with larger diameters in the upper half-ring bristles (21) and lower half-ring bristles (22) have a greater tilt angle.

4. The brush seal structure for the bearing pivot of an extruded oil film bearing as described in claim 1, characterized in that, The front plate (11) and the back plate (13) are fixed by snap-fit ​​or welding.

5. The brush seal structure for a squeeze film damper bearing support point of claim 1, wherein, The rotor track (14) is provided with a coating (15) at the position matching the brush bristles (12).

Images